Here's one possible imagined explanation: The panel that went into that compression-crowned board was not fully cured, or not completely dried down prior to ribbing. Didn't have enough compression to crush wood cells during the wet season, and shrank as it dried and cured to produce negative crown instead of cracks. Commonly seen in "flat-top" guitars when the maker doesn't pay attention to shop humidity during the build. Mike On 12/7/2010 7:53 AM, Terry Farrell wrote: > Reminds me of my first adventure into piano technology (before I got > into the business). My brand new S&S 1098 with a full quarter-inch of > reverse crown - stretch a string across the back of the panel parallel > to ribs, let string touch panel in center and observe both ends a > quarter inch off the panel. I wish I remember whether I had taken any > string bearing measurements - however I seriously doubt it - would > have been interesting though. Dog-gone hard to imagine exactly what > might have caused such a condition. > > Terry Farrell > >> I have a 1990 Baldwin 6000 (52” upright) with an inverted soundboard. >> The piano was evidently in a very damp environment at one time, since >> there were several loose glue joints, including the bass bridge to >> apron and some plywood delaminating in the bottom board . The >> inversion is severe enough that the ribs near the center of the board >> are pushing against a back post. The tone is even but weak. Is there >> any way to flip the soundboard back to its original position without >> destroying it? Can I just remove some wood from the back post to give >> the rib clearance and expect that to enlarge the tone? Bearing can be >> adjusted because of the Accu-hitch pins. Thanks for any suggestions >> or prior experiences. >> >> Don Hubbs >
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